We study numerically the dynamics of an air-in-liquid compound drop impacting onto a solid surface. We demonstrate that the addition of a bubble in the drop decreases its maximum spreading. This decrease is explained by the lower kinetic energy of the drop, but also amplified by the formation of a vertical jet emerging from its center, and a relative increase in the viscous dissipation. We propose a new theory describing the maximum spreading of an air-in-liquid compound drop by including these effects into modified Weber and Reynolds numbers. Finally, we demonstrate that the eventual bursting of the bubble does not significantly affect the maximum spreading diameter, by characterizing the bubble bursting and performing additional simulations where the bursting of the bubble is prevented.

中文翻译：

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撞击式气液复合液滴的最大扩散

我们从数值上研究了液中空气复合液滴撞击固体表面的动力学。我们证明在液滴中添加气泡会降低其最大扩散。这种下降的原因是液滴的动能较低，但也可以通过从其中心形成的垂直射流和粘性耗散的相对增加来放大。我们提出了一种新理论，通过将这些影响包含到修改后的韦伯和雷诺数中来描述液体中空气化合物液滴的最大扩散。最后，我们证明了气泡的最终破裂不会显着影响最大传播直径，通过表征泡沫破裂并执行额外的模拟来防止泡沫破裂。